Ballast Bypass for E39 Corn Light

Video Transcript:

This instructional video will step you through the ballast bypass process to replace a traditional 400 watt metal-halide flood light with a more efficient 40 watt Star LED Semi-Corn Light. We removed the light housing to show you the process in a controlled environment. Here on our work bench, you can get a better close-up view of the process.


StarLED 300W Equivalent LED 180 “Corn” High Bay Light Bulb 45W=5000lm


You will want to flip the unit where you can access open the housing an easily access the electronics inside.
Here you can see the traditional 400 watt metal-halide light bulb. Make sure that you have given the light sufficient time to cool down since these bulbs can reach over 500 degrees. Next, you will want to remove the aluminum reflector. The reflector helps amplify and spread the light. Finally, you will want to remove the insulation.


In this unit, the insulation is a treated cardboard type material that has become dried out and brittle. Now you can see all the wires, the capacitor and ballast within the light unit. We take one last look at the metal-halide light bulb to get an idea of its size and fit. We now show you the replacement StarLED Semi-Corn Light Bulb. The back of the light bulb has aluminum fins to dissipate the heat from within the light bubs driver. You will also note that the light bulbs 120 volt to 277 volt AC requirement, output at 40 watts and the UL certification.


Outdoor Metal-Halide Flood Light


From the back you can see the hot wire in, neutral wire and the ground wire. These wires go directly to the ballast. We are going to pull the wires back into the housing since we want to replace the power cable also. Note that the white wires go into the ballast and the green wire is grounded to the inside of the housing. Here we show you the new power cable with a black hot wire, white neutral wire and a green ground wire.


Outdoor Metal-Halide Flood Light


We will push it through the back and into the housing. We want to replace the old wire nuts with new ones. We will fist connect the ground wires together. Next we will want to connect the neutral wire from the power cord directly to the white neutral wire going to the E39 socket. Finally, we connect the black hot wire to the wire directly attached to the E39 socket. Now that we have completed the ballast bypass part, we will re-assemble the flood light in reverse order.


First we put back the insulated heat paper. Next we will want to put the aluminum reflector back into place. After that is done, we can screw in the new StarLED Semi-Corn light and angle the light by back turning it into place. We suggest that you replace the water tight rubber stripping before closing the housing. Now you are ready to re-install the flood light to the desired location. We invite you to check out all of our E39 socket high bay lights and corn lights at